1. Field of the Invention
This invention relates to liquid rocket propulsion systems and is particularly directed to liquid rocket propulsion systems for spin-stabilized and other small vehicles.
2. Description of the Prior Art
Liquid or fluid-fueled rocket engines have been known for many years and have been the primary propulsion system for virtually all of the world's exploration of space. In fact, in any rocket program which requires high performance and low weight, liquid or fluid-fueled rockets have been preferred over solid rockets. Furthermore, liquid rockets may be started and stopped, substantially as desired, whereas solid rockets are usually one-shot devices. On the other hand, liquid rockets are, inherently, much more bulky than solid rockets. Consequently, where size is an important factor, solid rockets are often preferred. For military purposes, size is often a major consideration since problems of deployment and concealment are directly related to size. Moreover, for those rockets which are intended for missions that are conducted primarily within the earth's atmosphere, increases in size usually cause increases in frontal area and, hence, increase drag and decrease performance. Therefore, solid rockets have usually been preferred for military purposes.
An additional disadvantage of liquid or fluid-fueled rockets has been complexity. Storage tanks are required for the fuel and some means, such as pressurization, a positive expulsion mechanism or the like, has been needed to deliver the fuel from the storage tanks to the thrust chamber. Frequently, high performance pumps, sophisticated valves and elaborate plumbing are required for such fuel delivery systems. Obviously, this adds to the weight and bulk of the liquid rocket propulsion system.